Beware of Invasive Cane Toads: Huge Toad is a Dog and Koi Killer

ALERT • JULY, 2014
Beware of Invasive Cane Toads: Huge Toad is a Dog and Koi Killer
Doug Caldwell, Ph.D. ■ U.F. Commercial Landscape Horticulture Extension, Collier County
Toxic Cane Toads are Everywhere!
INITIAL TREATMENT
Be careful when walking your dogs in South Florida.
Don’t let them stray into the bushes or nose around
without supervision. Especially at night! They may find
a toxic Cane Toad.
Flush the toxins away from its mouth (not into its
stomach). Use a hose and squirt so the water drains out
of the mouth. Take a wash cloth and try to clean the
gums and mouth as you rinse
the poison away. Do this for
15-20 minutes then get to the
veterinarian.
Check Your Yard
Photo: Think Fish Media © 2004-2013
This toad defends itself using
chemical warfare. When
disturbed, it releases
(sometimes squirts) milky
toxins that will burn the eyes,
inflame the skin, and are
rapidly absorbed across the
mucus membranes of the
victim into the circulatory
system. If your pet bites or
swallows a Cane Toad, it will
become sick and may die in as
little as 15 minutes unless you
take immediate action.
SYMPTOMS
The first indication of a problem is pawing at the mouth
and frantic, disoriented behavior. The mucus
membranes turn a brick red (instead of pink) and the
animal will foam profusely at the mouth. Other
symptoms include vomiting, head-shaking, crying, loss
of coordination and sometimes convulsions.
If you have pets it is a good
idea to catch and identify ANY
toad you see in your yard to be
sure that they aren't dangerous.
With very few exceptions, any
toad in Florida that is larger
than 4 inches is NOT native
and is almost certainly an
invasive Cane Toad.
Wear gloves to protect yourself
and catch them in a net.
Humanely euthanize any Cane Toad by spraying 20%
benzocaine sunburn spray on the toad's lower belly. In
a few minutes, it will become unconscious. Place it in a
sealed baggy and freeze for about a week. Discard in
the trash the day it will be picked up.
More detailed information on following pages...
Good Toad • Bad Toad: Naples Reporting Increasing Numbers of Cane Toads
A South Naples (off Davis Blvd) resident warned me
that they were seeing large numbers of these toads. He
had collected a dozen in an hour! So, I had to see if my
dog's exercise habitat was a toad gauntlet. I went for a
10:00 p.m. walk and found 8 in 30 minutes! When we
have rainy, rainy seasons and mild winters, frog and toad
populations will most likely abound. Dog lovers,
snowbirds especially, need to be careful when walking
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your dog in south Florida. Don’t let
them stray into the bushes or nose
around without supervision! They
may find a toxic toad, the cane toad!
Dogs especially may want to chew
on it or eat it, which could end up
requiring a visit to the pet
emergency hospital. For small pets
and wild animals, this toad toxin
could be deadly. These toads will
also climb into outdoor food bowls
to consume leftovers, which may
also lead to a confrontation with
Fido. So sanitation is important in
reducing possible encounters.
Cane Toad Size
It may have escaped from zoos or pet
stores and/or was released as a
biocontrol agent for large beetles in
sugarcane fields, hence the “cane”
name. However, University of
Florida, Sugarcane Entomologist, Dr.
Ron Cherry, doubts the toads have
diminished the beetle populations.
And Les Baucum, UF Regional
Sugarcane Extension Agent states, “I
have spent many, many hours in
and around sugarcane fields and
have NEVER seen a cane toad.”
These toads were intentionally
released in 1935 in Australian
sugarcane fields for beetle control
and it has become an ecological
nightmare there (see references at
end of article) with no beetle control
benefits either.
Toad I.D.
Do not confuse these bad toads with
our native, southern toad, Anaxyrus
terrestris, previously Bufo terrestris.
The southern toad stays under 4
Photo: Doug Caldwell
Photo: U.S. Geological Survey
Adults of the cane toad (AKA,
marine toad) or Rhinella marina,
previously Bufo marinus, are the
largest toad found in the US. It grows
from a tadpole to a 6 to 9 inch long
toad; this is just the body without the
legs extended! The Guinness Book
of Records reports a pet cane toad
record length of 15 inches body
length and weighed in at 5.84
pounds. There are urban legends
about how this toad, which is
naturally found in south Texas
through Mexico and South America,
wound up in south Florida.
Native Southern Toad
The Southern Toad stays under 4 inches in
length. It also has smaller oval parotoid
glands and two short, parallel ridges that
start as knobs between the eyes and extend
down the back.
Invasive Poisonous Cane Toad
The invasive Cane Toad has no knobs or ridges between the
eyes. There are 2 larger triangular parotoid glands located just
below the shoulders. Many grow to the size of a salad plate and
become up to four pounds in weight.
Helping you Beautify your Landscape and Protect the Environment
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wide variety of toxins secreted by
this toad.
Toxin being released from the
parotoid glands of the Cane Toad.
inches in length. The southern toad
also has smaller parotoid glands and
two short, parallel ridges that start as
knobs between the eyes and extend
down the back for an inch or so. The
cane toad has no knobs or ridges
between the eyes. The cane toad has
dry, warty skin and the color is
usually various shades of brown with
some grey, some are yellow, redbrown or olive brown with varying
brown and white mottling.
Poisonous Pest!
This toad defends itself using
chemical warfare. When disturbed, it
releases (sometimes squirts if
stepped on) toxins. These toxins are
secreted in a milky substance from
the toad’s large parotoid glands,
which are an aggregation of granular
glands (modified mucous glands)
located at the back of the head,
behind and to the side of each ear
drum (tympanum). These toxins
will burn the eyes, inflame the skin,
and are rapidly absorbed across the
mucus membranes of the victim into
the circulatory system. There is a
A female deposits batches of 8,000 to
25,000 eggs and the gelatinous egg
strings can stretch up to 66 feet in
length. Eggs are deposited in water
and hatch into tadpoles within 2 to 3
days and become land dwelling
toadlets in 45 to 50 days. The toads
can live 10 to 15 years. All parts of
the Cane Toad are poisonous–eggs,
juveniles and adults.
Dog Killers
Dogs (especially certain breeds such
as terriers and Jack Russells), tend to
be curious and if they latch onto one
of these big toads there can be
serious health consequences. The
first indication of a problem is
pawing at the mouth and frantic,
disoriented behavior. The mucus
membranes turn a brick red (instead
Symptoms & First Aid
If your dog exhibits these symptoms
it is crucial to immediately flush the
toxins away from its mouth (not into
its stomach). Use a hose and squirt
so the water drains out of the mouth
for about 15 minutes. Mixing
hydrogen peroxide with water 50:50
as a final rinse may help deactivate
the toxin. Take a wash cloth and try
to clean the gums and mouth as you
rinse the poison away. Then get to
the veterinarian. If the toad was
swallowed, it must be removed,
either surgically or with an
© NSW Government, Australia
Photo: Leong Tzi Ming
Rapid Reproduction
of pink) and the animal will foam
profusely at the mouth; often vomit;
and may vocalize and the eyes may
move rapidly back and forth.
Convulsions are not uncommon.
This may progress to stupor and
death, especially with smaller dogs.
Death may occur in as little as 15
minutes due to cardiac arrhythmia.
A female deposits batches of 8,000 to 25,000 eggs and the gelatinous egg
strings can stretch up to 66 feet in length. Beware! they are poisonous.
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eggs or if simply the presence of the
eggs was toxic to the koi.
endoscope. Fido’s temperature
should be monitored because
dangerously high temperature often
follows the intense muscular activity
induced by the toxins.
What To Do
Mike Freedman, Horticulturist from
Fairchild Tropical Botanic Garden
states, "The toads are exotic and
dangerous and should be removed
from the U.S., but with a cool head."
Thanks to Dr. Joshua Parra, Florida
Veterinary Referral Center (Estero)
for sharing cane toad experiences.
Fish Deaths
In March 2012, a local hotelier
reported a koi incident: “Our pond
is 250 gallons and we lost 8-10 koi.
We were maintaining the water
feature of the pond and my tech
moved one of the rocks that is a
part of this feature and exposed a
nest with about 10 black toads all
of which proceeded to seek shelter
in the pond–30 minutes later all
the koi went belly up. Strangely
enough, we have 2 plecostomus
(bottom feeder), which were fine.”
Partial catch from June 2014
neighborhood Cane Toad hunt–
37 Toads collected in one hour on
a one mile hike.
Since this is not direct contact on
land, it seems like an unexpected
event, but the literature reports koi
ponds with eggs (and possibly the
tadpoles) of cane toads can kill koi
fish. In several cases, koi have died in
a small pond within 24 hours after a
cane toad laid its eggs in that pond. It
was unclear if the fish had eaten the
More Reading References:
http://edis.ifas.ufl.edu/pdffiles/UW/UW34500.pdf
http://ufwildlife.ifas.ufl.edu/frogs/canetoad.shtml
You might even work on helping
reduce the cane toad populations by
having neighborhood hunts. To
catch a cane toad, use gloves and a
fish or butterfly net. You may
humanely euthanize any cane toad
by spraying 20% benzocaine
sunburn spray on the toad's lower
belly. In a few minutes, it will
become unconscious. Place in a
baggy and freeze for about a week
and discard in the trash the day it
will be picked up. Subscribe to My
Newsletter at this
Link
http://eepurl.com/Q7K5D
http://www.critterology.com/bufo_toads_poisonous_to_pets-226.html
Click this link to hear this toad’s particular song:
http://www.wec.ufl.edu/extension/wildlife_info/frogstoads/rhinella_marina.php
A 5-part Australian video series: Cane Toads an Unnatural History
http://www.youtube.com/watch?v=v6ERCHFlN1A&feature=relmfu
Doug Caldwell is a Certified Arborist and the commercial horticulture extension agent and landscape entomologist with the University of Florida Collier
County Extension Service. The Cooperative Extension Service is an off-campus branch of the University of Florida, Institute of the Food and
Agricultural Sciences and a department of the Public Services Division of Collier County government. Extension programs are open to all persons
without regard to race, color, creed, sex, handicap or national origin.
For updates on the Southwest Florida horticulture visit: http://collier.ifas.ufl.edu
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